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Auto body paint mixing room classification?

Question asked by gil.davis on Aug 1, 2018
Latest reply on Aug 9, 2018 by gil.davis

Hi everyone, I am new to the board here, so please forgive any rookie mistakes in routing. But I have a bit of a complex questions, maybe someone can point me in the right direction. I work for a company that manufactures and supplies automotive paint mixing scales and terminals to the auto body industry. Typically for the last four decades or more we have supplied only Class I, Division 1 equipment to the market, but of late, some of our customers are expressing interest in us producing devices approved for CLI/DIV2.

Typically these devices are installed in a paint mixing room that is not bigger than maybe 6 ft X 10 ft, and it is our understanding that the accepted "unwritten" rule is that the entire mixing room is classified as C1D1. Does anybody have any input on whether or not this is true or not still?

In an attempt to save costs, our customers are considering switching to Div 2 devices, but this is a major concern. We are arguing that this is probably not smart, but they are seriously looking at taking the risk, penny wise and pound foolishly IMHO. We are still in the process of presenting our case to stick with C1D1, and if anyone has any thoughts with good reference where I might be able to find such info, much appreciated. I have already poured over NFPA30 and NFPA33, and it is quite exhaustive and in some cases, vague and open to interpretation by local authorities.


In a nutshell, they are arguing using NFPA 33 that there is the theoretical 3 ft bubble around the mixing scale itself where the paint/solvent is poured is Div 1, and then outside this 3 ft bubble is considered Div 2 where they would put a computer or controller approved for Div 2. They say that their evaluation teams (EH&S?) have determined that this is adequate, but if the entire room is C1D1, then their assumption is wrong. I just cannot seem to find any hard evidence that there is a national standard that is adhered to for this topic.


Any thoughts?